Semiconductor wafers are generally planarized or polished, in a planarizing or polishing machine, before thin films are applied using chemical vapor deposition (CVD), oxidation, or sputtering processes. In a typical planarizing or polishing machine, a polishing or buffing pad is adhesively attached to and covers the entire upper surface of a heavy rotatable platen. The platen is disposed atop a drive assembly which is disposed within a processing chamber of the machine. Semiconductor wafers to be processed, arc held in a support assembly which is vertically translated between a first position to a second position. In the first position, the wafer is disposed apart from and above the platen. In the second position, the wafer is in contact with the pad. During a planarizing or polishing operation, the drive assembly rotates the platen, thereby rotating the attached pad. The support assembly lowers the wafer from the first position, and into the second position, i.e., into rubbing contact with the rotating pad, thereby planarizing or polishing a surface of the wafer.
The pad is removed and replaced once or twice per twelve hour shift. In order to remove a pad, a technician reaches into the processing chamber of the machine to grasp and pull on a portion of the pad. In typical polishing or planarizing machines, the processing chamber is surrounded by walls forming a cabinet. An access opening is provided in one of the walls of the cabinet, and is formed approximately three feet above ground level. Since the platen and the pad are approximately two to three feet in diameter, a technician must reach approximately two to three feet into the processing chamber in order to grasp the distal portion of the pad. Also, because of the location of the access opening, the technician generally must bend over at the waist in order to pass his/her arms and upper body through the access opening and into the processing chamber. Once an adequate handhold on a portion of the pad is achieved and while remaining in the bent over position, the technician pulls on the pad, with a force of approximately 40-80 pounds, to peel it off the upper surface of the platen. The technician is exposed to substantial risk of lower back injury because she must exert a significant pulling force while bent over at the waist.
There is, therefore, a great need to provide a device or tool for assisting the technician in removing buffing and polishing pads from platens in semiconductor wafer planarizing or polishing machines.